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                                                              Exhibit 99.906CERT

                            SECTION 906 CERTIFICATION

                Certification Pursuant to 18 U.S.C. Section 1350,
                             As Adopted Pursuant to

                  Section 906 of the Sarbanes-Oxley Act of 2002

Morgan Stanley High Yield Securities Inc.

     In connection with the Report on Form N-CSR (the "Report") of the
above-named issuer for the period ended August 31, 2005 that is accompanied by
this certification, the undersigned hereby certifies that:

1.   The Report fully complies with the requirements of Section 13(a) or 15(d)
     of the Securities Exchange Act of 1934; and

2.   The information contained in the Report fairly presents, in all material
     respects, the financial condition and results of operations of the Issuer.


Date: October 20, 2005                      /s/ Ronald E. Robison
                                            ---------------------
                                            Ronald E. Robison
                                            Principal Executive Officer


A signed original of this written statement required by Section 906 has been
provided to Morgan Stanley High Yield Securities Inc. and will be retained by
Morgan Stanley High Yield Securities Inc. and furnished to the Securities and
Exchange Commission or its staff upon request.

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                            SECTION 906 CERTIFICATION

                Certification Pursuant to 18 U.S.C. Section 1350,
                             As Adopted Pursuant to

                  Section 906 of the Sarbanes-Oxley Act of 2002

Morgan Stanley High Yield Securities Inc.

     In connection with the Report on Form N-CSR (the "Report") of the
above-named issuer for the period ended August 31, 2005 that is accompanied by
this certification, the undersigned hereby certifies that:

1.   The Report fully complies with the requirements of Section 13(a) or 15(d)
     of the Securities Exchange Act of 1934; and

2.   The information contained in the Report fairly presents, in all material
     respects, the financial condition and results of operations of the Issuer.


Date: October 20, 2005                      /s/ Francis Smith
                                            -----------------
                                            Francis Smith
                                            Principal Financial Officer


A signed original of this written statement required by Section 906 has been
provided to Morgan Stanley High Yield Securities Inc. and will be retained by
Morgan Stanley High Yield Securities Inc. and furnished to the Securities and
Exchange Commission or its staff upon request.